Glue type for cracked, not broken, maple neck

Thinner CA is stronger, both in how it penetrates surfaces and how hard it cures. I would only use thin CA for structural repairs in instances where I am using CA.

I'm not entirely following what it is you're fixing, but this doesn't sound like an instance where I would use CA.

Cracked neck... do you mean a peghead break? I'd definitely use Titebond for that. I like the original stuff. You'd be surprised how far that can work into places. It doesn't wick, but it does sort of pump into areas, so you can keep pressing it in and it'll slowly work in, and as you open and close the crack, it'll push back out, but some of it will also push deeper into the crack. The difficulty of such a repair is generally getting good clamping rather than the glue application, so I'd focus on that.

Background and my decision to chicken out: I contacted a local luthier about repairing/gluing the crack of this neck, which is part of a MIJ reissue 1950s Hot Rod with a Floyd Rose trem. I bought the guitar a few years ago; it arrived like this, a surprise, but I wanted to keep it, so I did. But, procrastinated on this repair for a long while. Now I'm sort of gearing up to unload several guitars... sometime. This one is "going" for sure. The luthier here is a really nice guy, whose opined that he'd do nothing, thinking that it would probably be OK and that if things got worse then a repair could be done. This was one of three options he mentioned. Being sort of anal, I thought it should be repaired. I've been watching YouTube videos for two or three hours, and thinking really hard about this. I've concluded that perhaps doing nothing would be best. However, knowing that I'm going to unload the guitar sort of makes me hesitate to sell it as-is.

Anyway, here's a link to my imgur album. Hopefully this works, as I'll have to create an additional post or two if it doesn't, since there's really no opportunity to edit on this site. I'm trying to post a link only to six photos, and hopefully not have the photos appear directly here:

imgur.com/a/13mKCIY#455Tq49

BTW, here's the "watering" video:

Here's a video that mirrors what I had in mind, except for the glue type:


I think thinned out Titebond wood glue would probably be best if I were to try this. However, even with prudent flexing of the neck (hopefully not creating further damage) would still not allow significant injection or flowing in of any glue.

So, I think I'm just going to put the guitar back together and string it up. I appreciate you guys reading and replying.

"Titebond is an amazing glue. No one ever wants to think so."

Yes it is!

If you're thinning it, don't go more than 6:1 Titebond:water or you'll substantially reduce bond strength.

The Titebond engineers advise a 5% water number will thin it and still allow the glue to retain all its original bond strength. The reason it's sold thicker is to help reduce running during the application process.

Still not having seen the crack, I'll venture a guess on how I'd approach the repair.

1. Unstring the guitar.

2. Relax the truss rod all the way.

3. Set up the neck on a clamp jig and apply clamp(s) to open the crack as much as posssible without doing further damage to the neck.

4. Put on safety goggles.

5. Apply a bead of glue along the crack.

6. Use an air nozzle on the end of a compressor hose to blow the glue deep into the crack while holding a towel over the work to prevent blowing glue all over your shop. NOTE: More glue will go flying away than you'll actually get into the crack, but that's the price you pay for success.

7. Run your finger along the crack to press remaining glue in.

8. Unclamp the neck from the jig and apply clamps to press the crack together.

9. Wipe up all squeeze-out with a slightly damp paper towel, dry enverything off, and go have a refreshing beverage.

Titebond is actually incredibly viscous. My material physics understanding isn't sophisticated enough to explain how something can be thick and gooey and very viscous at the same time (probably has something to do with surface tension, kinda like dish soap) so I guess you'll have to take my word on it. I've gotten Titebond into tight places like that plenty of times. The old stuff becomes stringy and weird and I wouldn't expect it to work well, but the new stuff is great. (if anyone doubts me, grab that 9 year old bottle off the shelf, buy a new bottle, and compare the two just in feel between your fingers. The difference will be obvious at that point.)

I use feeler gauges fairly often, but this isn't an instance where I'd use one. I don't think floss would work well. Syringes are great, but I don't think this is a good application. The guy in the video you linked is using a liquid hide glue. Normal hide glue is necessarily hot, but the liquid stuff is stabilized to be in a bottle like regular glues; a common trick among woodworkers is to heat liquid hide glue (not to be confused with hot hide glue which HAS to be heated) to thin it way out without diluting. I think that approach could work sans the syringe, though maybe the syringe was mainly for the sake of heating the glue rather than the application. The issue with either the syringe or the feeler gauges in this instance is that there is no point of entry for the tool, and you'll likely munge up the wood around the edge of the crack in the process. If I had the SG from the video, my first choice would be working in the Titebond, second choice the warm hide glue, but I'd clamp it properly with blocks instead of the shortcut method I mentioned above.

I like the air compressor idea, but if you go that route I'd offer two tips: 1) don't use the cans. It likely won't matter with this neck, but the cans have bitterant and that weird cold stuff in there, and can do weird things to finish. In fact, you can actually "relic" a lacquer guitar very quickly if you hold those cans upside down so it sends out the cool air. It will give instant checking. 2) do your squeegeeing and stuff first and save the air for close to the last step before clamping. If you have dry air, it could reduce the work time a bit; probably not a realistic concern, but better safe than sorry.



Are you confusing vises and clamps? I think we've only been talking about clamps thus far.

Close-up views of post hole. One shot (last) clearly shows a partial transverse fracture line.

Link to imgur album:

imgur.com/a/fXOMgNu

Good plan. If it were my guitar and I couldn't get 'em to open up readily then I'd probably just use the thin CA and be happy enough. Those don't look like they're gonna disappear without sanding and refinishing anyway.
Whatever you do, don't use C-clamps without cauls like that dude in the video; they are guaranteed to leave marks.
I did look up the water and CA thing and evidently it works as a bit of an accelerant and supposedly makes a stronger bond. I'm skeptical of that last bit...

It looks to me like the cracks are deeper than they seem. The top part is dark because of the dirt and hand oil that has worked its way into the cracks over time while the area in the holes has been left untouched. It could be an optic illusion, but I think I see the cracks running down into the holes. Do you have naphtha or mineral spirits handy? If you drop some into the crack it will wick in and make the crack dark until it evaporates. It won't hurt the wood or compromise an eventual repair, unless you try applying glue before it has a chance to completely dry. You might get lucky and flush out some of that grime, too.

With all respect to your luthier friend, I'd skip both the vise and the blow dryer. I have a padded vise as the center piece of my bench and while I don't think it is a *bad* idea, I probably wouldn't use it in this instance and I certainly wouldn't lose sleep over not having it. A blow dryer won't provide enough heat to make hard maple more flexible. Usually when wood is getting more bendy with heat it is because it is softening structural glue joints (for example, fingerboard joints when heat pressing a neck); to get enough heat on that to actually make it more flexible you'd likely leave burn marks. But, it wouldn't hurt if you want to give it a shot. I would avoid using the dryer after applying glue, though. When you hit Titebond with a blow dryer it goes to a weird semi-dry state where you can still work with it, but it isn't all that friendly and your open time goes down to mere seconds. I run into this sometimes with binding repairs.

I can't see enough of the neck to know its grain orientation, but grain can have direction and all sorts of qualities that aren't immediately obvious from the growth rings, like tangential or radial lines where fractures are possible. My guess is it is some sort of grain run out being emphasized by the changing contour of the neck/peghead. If the color of the neck seems to change a lot when you turn it from end to end, then it probably has some grain run out, which means the length of the neck isn't necessarily the same as the length of the tree, but is sort of canted at an angle within it - this often happens to increase yield and/or to cut around imperfections. It isn't a factory issue. Grain run out on a maple neck isn't a big deal, I only point it out because it might explain the exact direction of this particular crack. The most likely explanation is the guitar took a face plant with string tension at some point. This can happen even if it is in its case or if it lands on soft carpet and leaving no marks, so it is still possible if you're the original owner and have zero recollection of it happening.

For what its worth, I'm still leaning towards my suspension bridge method after seeing more pictures and hearing more about it. Use non marring blocks under the peghead and the trunk of the neck, the crack area suspended over a bench. With the fingerboard down, you can place a clamp over the crack area bending the whole neck down, and the crack will naturally close using the spring tension of the entire neck instead of having to precisely press the crack with carefully formed cauls. If you use a qwik-grip or similar, you won't even need any cauls. (I would do a couple tests to make sure that they're strong enough - they're often weaker than they seem, though the newer ones I've seen are a bit stronger. If the neck is noticeably deflecting toward the table, you're probably fine. You can also feel over the crack and feel if it seems flush.) Some newer F-clamps come with plastic feet on them that on their own wouldn't be enough, but combined with a thick piece of leather might be adequate. A block would be best. Wax paper or parchment paper will keep you from gluing your block to the neck. If you *do* glue the block to the neck, it is easier to fix than it seems (don't ask how I know this ).

I don't think the glue wicking is going to be an issue, either. If you want to have something lined up as a just-in-case, keep a water spray bottle handy. If you're pressing the glue in and it doesn't seem to be doing much, give the neck a spritz. That will introduce enough water to thin out the glue a bit, but not enough to make it much weaker. That said, I've gotten glue into cracks like this a lot of times and thought that I wasn't doing much, but then when I get the clamps on I get a really nice little line of squeeze out which tells me there was way more in there than I thought. Remember that part of how wood glue works is by being able to sink into very, very fine parts of grain, making the glue line often more strong than the glue itself.  If it was too gooey to sink in, then it would fail all of those strength tests.  Incidentally, this is why glues like epoxy can sometimes be weaker, despite the hardened glue itself being ridiculously hard.

*Also adding I'm not paid by the good folks of Franklin for praising their Titebond products. But, if they want to send me money, I won't argue. I like money.

I beg your pardon!



I use Original on everything and it is the standard for the music biz, though a few guys on here like having all of them and going between them. The biggest advantage to moving away from the original for the woodworking/hobby world at large is in the water proofing, but that's a non issue on guitars... at least, if the guitar experiences that much water exposure, you're going to have bigger issues than moistened glue joints. The Elmers is fine as far as I know, but I've never really heard anyone worry about comparing the two of them. If I had both in front of me, I'd pick whichever one was fresher since that is a known issue for me with either brand. If you find good scientific comparisons among different brands of basic wood glue I'd love to have a look, even though I have no reason to stray from my beloved beige and red bottles.

The vise you're looking at is a joinery vise, and while it would work, you'd have to add some leather or plastic pads, and it might not be heavy enough to withstand you yanking on it with a neck in it. Unless you had a full-on Roubo, you'd probably end up picking up the whole bench when you yank on it. The one that your friend was likely referring to is expensive, needs to be mounted to a table with a large hole, and not worth it. I get where you're coming from with the gravity, but the wicking action up the crack will be strong enough that you could do it entirely upside down and get the same result. My vise is the older version of this: www.stewmac.com/luthier-tools-and-supplies/types-of-tools/vises/guitar-repair-vise.html Those actually started as generic woodworking vises but guitar people loved them so much that most people assume they're a guitar world creation.

If I was hell bent on having a third hand, I'd see if there was a flat front bench I could clamp it to with a caul and a C clamp.

If the issue is just a third hand, you might be able to approximate a face vise if you have a bench front that you can clamp to, like a large table apron hanging down. Or, clamp the neck to a table top hanging over the edge.

I think you'll be fine with that choice.